We have a 5508 that has just been upgraded from 7.0.240 to 7.6.100 with many 1142's, 3502's, etc. Our wired network is HP 5406zl's POE on every port and plenty of power available for POE.
As soon as we upgraded our 1142's to 7.6.100 we started getting poe faults on several switchports. The trap indicates an over-current error and the AP will not power up. I can move that same AP to another switch port and some times that will work. If I reboot the switch the faults may clear on those ports, but will reappear on other ports. It is not always the same APs, and not always the same switch ports.
I have tried downgrading back to 7.0 and the errors clear. Obviously I want to be running the newer code for the bug fixes and features. TAC has not given this case any time yet.
The switches report more than enough power being available still on the ports. I can see the ports try to come up, and most of the times the AP will start to power up and come up at 8 watts as it boots, and as soon as the AP is ready to go and starts powering the radios it enters the fault state.
The APs all run in local mode, and I have tried enabling "Pre-standard 802.3af switches. "
Does anyone have any ideas? Something must have changed in the way power is drawn or negotiated.